The broad objective of the project is to understand what the actions of the various steroid and peptide (LH, FSH, prolactin) hormones are and how these effects are mediated. Currently under study are two models of steroid hormone resistance; glucocorticoid resistance in the New Word primates, and glucocorticoid resistance in man. Both of these forms of glucocorticoid reistance have been found to be due to defective glucocorticoid receptors. Also unde study are the extramammary actions of prolactin. In particular, the effectof prolactin on hypothalamic-pituitary-gonadal function is currently nder investigation.